1. Field of the Invention
This application relates to a marker holder clip which is adapted to accurately position and retain a recorder instrument marker having a hinged holding member that is designed to lock against a portion of the marker body. Such markers are sometimes referred to in the art as "clip-on" markers.
2. Discussion of the Prior Art
Various means have been employed to secure instrument pens or markers onto the holders or arms of recording instruments. For instance, in U.S. Pat. No. 4,048,640 (Caldwell), a pen cartridge and pen mounting arm are disclosed wherein one end of the mounting arm comprises a notch formed therein and a pair of stop shoulders are provided on opposed sides of the arm to cooperate with a mating assembly on the ink pen cartridge when the arm and cartridge are engaged.
In U.S. Pat. No. 4,024,547 (Raahauge) an instrument recorder pen is disclosed that includes an ink cartridge having spaced apart lugs on the underside thereof to receive a marker support arm. As can be seen in FIG. 4 of this patent, the marker support arm itself has a generally convex surface portion which presses against the cartridge as the arm is engaged in the lugs.
Of further interest is U.S. Pat. No. 3,137,539 (Graham) wherein a pair of tab members are provided on the end of a stylus arm to position the marker. Of similar interest is U.S. Pat. No. 4,052,713 (Lytle et al) which discloses a universal snap mounting for disposable chart pens wherein one end of the recorder arm is provided with a "V" shaped notched end into which the writing nib is received. A spring clip 38 with tab portions 40, 44 "snap clips" the ink cartridge to the arm. Also, in U.S. Pat. No. 3,876,050 an armature structure for coupling a recorder pen and a reset spring in mosaic printing applications is disclosed. Here, the armature comprises a magnetic metal strip having a tubular portion formed in one end thereof and flanged edge portions at the other end thereof.
Other means for securing pens to their support arms may be seen in U.S. application Ser. No. 654,406 (Hubbard) allowed Feb. 24, 1978 and U.S. Pat. No. 3,983,569 (Hubbard et al), which patents are commonly assigned herewith.
Notwithstanding these prior art means for securing writing instruments to their holders, there remains a need in the art for a holder clip that can accurately position and reliably maintain the marker or pen under conditions of considerable disturbance, such as marker change of nearby positions on multi-marker recorders.
There is also a need for a holder clip which will substantially prevent any movement of the marker along the marker support arm axis.
There is a particular need for a holder clip which is adapted for use in conjunction with a "clip-on" type marker, such as that disclosed in U.S. Pat. No. 3,983,569, which clip will substantially eliminate marker movement along the support arm under conditions of considerable disturbance as caused by vibration or the change in marker positions on multi-marker recorder instruments.
These and other objects are met by the marker holder clip of the present invention, which may be better understood by reference to the following detailed description thereof, taken in conjunction with the appended claims and drawings.